Bump Maps and how to get more details in them
I would use a software like CrazyBump, Knald, or SmartNormal to create a normal map based on the image you have and add that to your material.

If you are using cycles you can run the normal map through a normal map node and plug that into your shaders.



Here's the result I got with SmartNormal.  You could improve a lot by spending more time tweaking the settings, but it's a start.